September 2008

The idea of a galactic habitable zone (GHZ) has a certain inevitability. After all, we talk about habitable zones around stars, so why not galaxies? A stellar habitable zone is usually considered to refer to those areas around the star where liquid water can exist on a planetary surface. Those who believe that confining habitable […]

As I taper back on my post-surgical medications (see yesterday’s post), a coherent universe is gradually coalescing around me once again. Still, I think I’ll take today relatively easy, looking at just one of the two stories I’ve been pondering during my brief convalescence. The first is intriguing not so much because of what it […]

Several interesting items in the news today but I won’t be able to get to them, try as I might. I’m just coming off surgery yesterday (minor), and although I’m otherwise fine, the pain medication I’m taking makes me so groggy that I hesitate to post. So bear with me until tomorrow, when I should […]

Using a near-infrared spectrograph attached to ESO’s Very Large Telescope, astronomers have been able to examine the inner protoplanetary disks around three interesting stars, with results showing the sheer diversity of the apparently emerging systems. Only a few million years old, all three stars could be considered analogs of our own Sun, going through processes […]

The idea that life on Earth might have originated elsewhere, on Mars, for example, has gained currency in recent times as we’ve learned more about the transfer of materials between planets. Mars cooled before the Earth and may well have become habitable at a time when our planet was not. There seems nothing particularly outrageous […]

What should be the goals of the next generation of X Prizes? Peter Diamandis is just the man to ask the question. It was Diamandis’ foundation that led to the launch of a private manned spacecraft in 2004, and since then his team has gone on to sponsor an automotive X Prize offering $10 million […]

A massive gamma-ray burst detected last March, believed to be the brightest ever seen, turns out to have been aimed directly at the Earth. A narrow jet that drove material toward us at 99.99995 of the speed of light is revealed in the data, itself wrapped within a somewhat slower and wider jet. The best […]

Who would have thought the planet Mercury would prove so useful in explaining how solar sails work? The Messenger spacecraft’s recent course adjustment maneuvers have proven unnecessary because controllers have been able to use its solar panels creatively, harnessing solar radiation pressure (SRP). And what better place to shake out such methods but on your […]

Making contact with an extraterrestrial civilization, whether by microwave, laser or neutrino, highlights the problem of time. Suppose you are looking for a newly emerging technological culture around another star. When do you transmit? After all, even the most powerful signal sent to Earth a million years ago would have no listeners, which is why […]

Fine work by Rosetta on the Steins flyby. Check here for more imagery of the ‘diamond in the sky,’ with cratering suggesting extreme age. Image: Asteroid Steins seen from a distance of 800 km, taken by the OSIRIS imaging system from two different perspectives. The effective diameter of the asteroid is 5 km, approximately as […]

Charter

In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For the last nine years, this site has coordinated its efforts with the Tau Zero Foundation, and now serves as the Foundation's news forum. In the logo above, the leftmost star is Alpha Centauri, a triple system closer than any other star, and a primary target for early interstellar probes. To its right is Beta Centauri (not a part of the Alpha Centauri system), with Beta, Gamma, Delta and Epsilon Crucis, stars in the Southern Cross, visible at the far right (image: Marco Lorenzi).

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